Getting Started

Foundation provides composable building blocks for resilient Elixir applications. This guide walks you through installation and your first retry loop.

Installation

Add foundation to your dependencies in mix.exs:

def deps do
  [
    {:foundation, "~> 0.2.1"}
  ]
end

Then fetch the dependency:

mix deps.get

Note: Foundation 0.2+ is a complete rewrite and is not compatible with the 0.1.x series. If you are upgrading, see the Migration Guide.

Your First Retry Loop

The simplest way to add retry logic is with Foundation.Retry:

alias Foundation.{Backoff, Retry}

# 1. Define a backoff policy
backoff = Backoff.Policy.new(
  strategy: :exponential,
  base_ms: 100,
  max_ms: 5_000
)

# 2. Define a retry policy
policy = Retry.Policy.new(
  max_attempts: 5,
  backoff: backoff,
  retry_on: fn
    {:error, :timeout} -> true
    {:error, :rate_limited} -> true
    _ -> false
  end
)

# 3. Run your function with automatic retries
{result, _state} = Retry.run(fn -> call_api() end, policy)

That's it. Foundation handles the delay calculation, attempt counting, and timeout enforcement.

What's Next?

Foundation is organized around a small set of focused primitives:

Each guide includes complete examples and configuration options.